on fire !!!

[ynotbiker]

Hi all , well im still bikeless. I did eventually get a new igniter and coil off ebay. Fitted them yesterday and the bike seemed ok but I could smell a bit of fuel coming from the exhaust. Off I went and got about 4 miles when no 2 coil got burnt out again Im not mechanically minded at all and it just seemed like a plug and play job. Anyone know what ive done wrong ??? Burning coils will turn out expensive.Any help would be much appreciated. NB couldn't find any faults in the wiring. Don't know about the big loom that runs right through the bike as it was well taped up from the manufacturers.cheers tony

[Mustang]

the coils get there 12 volts from the ecu ,
the transistors in the ecu switch the 12 volts to the coils on and off just the same as a old set of Lucas points .
if it ran fine at first and then acted up you may have gotten a bad unit from ebay
a shorted wiring harness is likely NOT  the problem but do check the leads plus and minus to coil #2 with an multi meter set to ohms and see if there is continuity between the leads and also check each lead for grounding to the frame by placing the neg lead of meter to frame and the red lead from meter to each wire you want to check . if your meter is digital you should see a 0 if no shorts .
before you do anything to bike you should check the "+" and "-" leads at coil 1, 2 ,and three and see what they show for volts .
volts should only be present when the transistors switch it on from the ecu .
you should see it switching on a multi meter while cranking engine with spark plugs unhooked to prevent starting .
check each set of 12 volt leads at all three coils.

if any of the above is over your skill level .................it's time to get it to a shop and let them fix it .

[ynotbiker]

thank you mustang but the above is way beyond my capabilities. This afternoon I put another coil on , fool that I am, but never had a chance to take the bike for a ride because this time the bike starts if I keep the revs up but as soon as I stop revs it cuts out , so I didn't take it for a ride. Like you say I will have to get someone knowledgeable to look at it. It is quite hard round here to find someone as ive asked a few mechanics who have begged off saying they are too busy. I don't think they fix bikes anymore and only like charging people £160 for dropping oil and £50 to change your tyres. if anyone knows anyone in the northeast of England I would appreciate it don't care how much it costs. I know this sounds sad but ive never had a bike that feels part of me, and ive had a few so really want me steamer back on the road. I think most of you know what I mean.

[ynotbiker]

got a man with a brain coming and meter one night this week fingers crossed.

[Sin_Tiger]

Glad to read that, I have a black box but I'm too far away to be of any help. Fingers crossed indeed.

[ynotbiker]

Hi all the plot thickens. The man with the brain and the meter came and checked all the wiring and all was fine. I think what the biggest numty on the site did was plugged the old ecu unit in when I went for the ride and broke down. Because today he set off with the other one on with a small bottle off petrol tied to the handle bars used as a tank so that he could check if the coils heated up and they didn't.So when he left I put the tank back on thinking everything was hunky dory again. now everything is back together when I start the bike and  put full lock on to the right the engine cuts out. maybe ive got an ignition problem now , I cant see that ive trapped any wires when I put the tank back on or if anythings tight . Again any help would be appreciated lads.

[London_Phil]

Hi There

Feeling your pain Bro.
Does it cut out regardless of which way the bars turn.? Cuts out instantly?, or coughs and splutters?.
If instant, likely to be wiring. Cable for ignition switch can fracture, and fail. and of course cutout switch, or any wiring to handlebar switches.
Any other electrical items stop when engine dies, lights indicators etc etc.
Sorry for the Spanish inquisition type questions, (of course, no-one expects the Spanish Inquisition)..... but remote diagnostics are not easy, as it were.

Regards

Phil

[rf9rider]

Sounds like a problem with the wires to the ignition switch.

Check the connector on the end of the loom that comes from the ignition switch, they can get dirty and corrode.

Then check the wires at the switch end, they can break.

[Sin_Tiger]

Another possibility that Ive seen before, the cut off switch on the right bar. I've seen a situation where the switch plastic had cracked inside where the contacts moved enough to go open circuit for just a split second if any pressure was put on the bars. You can link out the two wires at the multi plug in the right hand fairing to check. Or it could even be just a poor connection in the multi plug, sometimes it takes very little stress on these to make a poor connection a failure.

[ynotbiker]

well sorted the cutting out trapped choke cable,anyways think I bought bad igniter off ebay burnt out coil again  ive got a friend whos got a igniter off a 97 sprint st will this do the job for me. I hope so fed up now 

[Mustang]

what cylinder melted the original coil ?
what coil melted with the ebay igniter , same cylinder ?

[ynotbiker]

was coil 2 burnt out first time . When the lad came back last week he noticed that the right hand down exhaust pipe was only luke warm so we put the other ecu unit in the ebay one because I think 1st time I rode of with dodgy unit. He also changed all the plugs and new coil on number 2 but yesterday when I went out it was ok for 10 mile then was only running again on 2 cylinders. right hand down pipe luke warm again. so I am surmising before he comes again with his meter that its another coil. Hes bringing a ecu unit and coils off a 1997 sprint st will this be ok if this is the problem. Hope you understand all this.

[Sin_Tiger]

Should work well enough for diagnosis purposes but I wouldn't give it big licks as the advance curve will be different.

Pissed that I'm not home at the moment 

[ynotbiker]

hi all the lad has just left after looking over my bike. The ecu seems fine and the coils fine. Anyway he was looking round and found that the tank breather hose was blocked at the small metal spiggot. He tried to take the spiggot off and it snapped, half is still in the tank. He thinks the problem is that water build up is getting into the petrol because of  blockage. The cause of the water build up is because a local mechanic who was going to work on my bike but didn't and just left it outside his workshop in the rain for a week so I just brought it home . Anyone know what I can do about the piece of spiggot still left in the tank. Maybe a very thin drill to unblock it and then some radweld to attach the other bit of spiggot to it. Im hoping this water is the problem. The burnt coil was a dodgy ecu but has been sorted now. Will empty the tank in next few days do I have to clean carbs also, and hopefully will be back on my tiger and ready to go to Scotland to meet some faces of the site.

[Mustang]

just twist a pc of wire up the drain hole , like a metal coat hanger wire, you should get a blob of crud out then the cap drain will work again
don't worry about the broken spigot the drain will function fine

carbs may need to just drain the float bowls which can be done without removing the carb bank .